This patch adds initial support for VFs on a new mac - X550.

The patch adds the basic structures and device IDs for the X550 VFs
that would allow the driver to load and pass traffic.
Signed-off-by: NEmil Tantilov <emil.s.tantilov@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>